U.S. energy firms this week added the most oil and natural gas rigs in a week since January as producers keep returning to the wellpad with crude prices trading around $45/bbl since late November.

The oil and gas rig count, an early indicator of future output, rose 15 to 338 in the week to Dec. 11, energy services firm Baker Hughes Co. said in its closely followed weekly report.

U.S. oil rigs rose 12 to 258 this week, while gas rigs rose the most in a week since April 2019, gaining four to 79, according to Baker Hughes data. Both oil and gas rigs hit their highest count since May.

Drillers began to return to the wellpad in August, after the number of operating rigs hit a record low of 244, according to Baker Hughes data going back to 1940.

Despite recent additions, the total rig count was on track for its biggest annual decline since 2015. This week it is down about 58% from 805 at the end of 2019, according to the data.

U.S. crude oil production has recovered from the two-and-a-half-year lows touched in May, but is still expected to decline by 910,000 bbl/d this year to 11.34 million bbl/d, the government forecast this week.

WTI, the U.S. crude benchmark, has risen about 148% over the past eight months on hopes that an effective coronavirus vaccine will revive global economies and energy demand. On Dec. 11, it was trading below $47/bbl, which is still down about 23% since the start of the year.